1. The Invention
This invention relates to 1-lower alkyl-4,5-dihydro-5-(phenyl and substituted phenyl)-2-alkoxycarbonylaminoimidazoles and pharmaceutically acceptable salts thereof and to methods of preparing such compounds. In a further aspect, this invention relates to 1-lower alkyl-4,5-dihydro-5-(phenyl and monosubstituted phenyl)-2-alkoxycarbonylaminoimidazoles, and pharmaceutically acceptable salts thereof, and methods of preparing such compounds. In a still further aspect, this invention relates to 1-lower alkyl-4,5-dihydro-5-(disubstituted phenyl)-2-alkoxycarbonylaminoimidazoles, and pharmaceutically acceptable salts thereof, and methods of preparing such compounds. In another aspect, this invention relates to 1-lower alkyl-4,5-dihydro-5-(methylenedioxyphenyl)-2-alkoxycarbonylaminoimidazoles , and pharmaceutically acceptable salts thereof, and methods of preparing such compounds.
This invention also relates to methods of treating or palliating abnormal conditions involving the central nervous system, in mammals, e.g., depression, anxiety, convulsions, centrally-induced skeletal muscle spasm and spasticity by the administration of the compounds of the invention.
2. The Prior Art
A general discussion of psychotic disorders and the use of psychotropic drugs can be found in The Pharmacological Basis of Therapeutics, 4th Edition, L. S. Goodman and A. Gilman eds., McMillan Co., New York (1970).
In 1973 a group of 2-amino-4-aryl-2-imidazolines were described in the Journal of Medicinal Chemistry, Vol. 16, No. 8, page 901 (1973), primarily as anti-hypertensive agents but were also tested for a number of other biological activities including whether the compounds reversed or prevented the effect of reserpine on mice. This publication indicated that some 2-amino-4-aryl-2-imidazolines prevented the effect of reserpine-induced ptosis, induced by the administration of 2 mg/kg of reserpine, whereas others were inactive in this test. In contrast to the compounds described in the Journal of Medicinal Chemistry, the compounds of the present invention are N-alkyl 2-alkoxycarbonylamino-4-aryl-2-imidazolines, a number of which have been found to exhibit the ability to reverse hypothermia and ptosis induced by 5 mg/kg reserpine in laboratory animals; two well accepted assay methods for identifying compounds of clinical utility in the treatment of endogenous depression. In addition, a number of compounds of the present invention display mild tranquilizing and/or sedating properties in behavioral assays, and/or they have the ability to protect animals against various kinds of experimentally induced, convulsive seizure states and further exhibit centrally acting skeletal muscle relaxant properties. This spectrum of activities indicates that the compounds of the present invention possess a unique activity profile unlike that of any currently known psychotropic agents.